If you saw Cher without the wigs, without the professional crazy makeup, without the lycra spandex clothing to hold her jiggly stuff still, I bet she'd look as old or older than Helen Mirren.
Here's one image of her without makeup. Plus she's had surgery. All you have to do is look at the old Sonny and Cher photos and she doesn't even look like the same person. That's plastic surgery that's not aging.
http://www.mirror.co.uk/3am/celebrity-news/cher-goes-with...
Here's Helen without makeup. I think she looks healthier and more naturally beautiful.
http://www.eonline.com/news/665344/helen-mirren-69-looks-...
Cher has also had a hard life. She's lived hard and had a rocker lifestyle some of it. That takes a toll on a person too.
I think if you want to spend the money on a face lift then go as natural as possible. Don't go crazy.
M. Osmond looks so very different. Her eyebrows are half way up her forehead. That's not what you want. Jennifer Gray only got her nose done and it was so normal that she couldn't get work for years. But she looked very good afterwards, no duck lips, no protruding chins or cheekbones, no harshness.
So if you do decide to have surgery do it only because you want to. Then google mishaps for plastic surgery. Look at what you might end up looking like. Then research the doc and figure out just how much you want to have done.
A little goes a long way if it's done right. A little goes waaaaayyyy toooooo far when it's done wrong.